The purpose is to determine whether language processing and expression deficits are associated with neuropathologies affecting subcortical structures and whether such language deficits contribute to such patients' speech motor control deficits Neurolinguistic studies of language functioning are aimed at analyzing the patterns of language deficits in patients with the following neuropathologies; Parkinson's disease, Hungtington's disease, and penetrating head injuries involving subcortical structures. The following issues are being addressed: whether the language processing deficits are related to disease duration, memory impairment ability to retrieve previously learned material, motor deficits, speech motor control deficits and, in the case of penetrating head injuries, the size and location of the subcortical lesion. At issue are whether different patterns of language impairment appear in different types of neuropathology and whether these vary independent of disorders of speech motor control. The language functions being addressed include: syntactic comprehension and formulation, naming, speecch repetition, word fluency, and reading and writing skills.